The present invention relates to security alarm systems, and more particularly, to a wireless security alarm system for detecting the unauthorized opening of a window or door to a protected area.
In the past, security alarms have typically involved complex circuitry and components which were difficult to install difficult or impossible to remove and use in other locations, and expensive to purchase. Wireless systems have been proposed and have included various sensors to determine the unauthorized opening of a window or a door to a protected area which would trigger a receiver alarm unit located somewhere else in the house or building. However, these units typically require a key switch to activate and deactivate the alarm unit to prohibit unauthorized persons from deactivating the alarm. The key switches are time consuming and inconvenient to operate.
Hand held control units have been provided with an emergency panic switch to trigger the alarm to summon help in the event an intruder is spotted in the dwelling or in the event of an illness or injury. These hand held units have also been provided with inhibit switches which temporarily deactivate the alarm to allow entry to and exit from the protected area without setting off the alarm. However, all of these wireless security alarm systems are fixed to the building, house or other object being protected so that they are difficult to remove and use in other locations. In addition, since these "fixed" units are difficult to install they are often very expensive to purchase. It is desirable to provide a wireless portable security alarm which is inexpensive, easy to manufacture and easy to install and reinstall in a variety of locations such as in homes, cars, boats, campers, trucks etc.